Bnking

I recently purchased an '85 928 S Euro car w/ a manual transmission. I haven't driven the car much because it has been in the shop for quite a while addressing many issues. I notice the car has a unique and bothersome exhaust odor (I know carbon monoxide is odorless). Additionally, the car sets off my digital carbon monoxide detector pretty quickly even with the garage door open. I am going to ask the mechanic if he noted any issues with, or modifications to the exhaust system, but I wasn't sure if the European cars came with different exhaust systems. I am guessing the regulations and exhaust systems were different for the US and Euro cars. I figured I'd see if anyone had some insight. Thanks

tv

You have a lot to learn, I suggest search function. Yes euro's have no O2 sensor and came from factory with NO cat. You must get all parts of the system working perfectly. The MAF, throttle body adj., plugs, dist.'s, throttle cable adj., wires, coils. (multiple sensors 3 I can think of + air filter)

Then get it on a dyno with exhaust gas reader and dial it in, helps to have adjustable FPR's. If dialed in right that is a fast (5sec car with best trans) and great sounding car.

The Forgotten On

It was optional for Euro cars to have a cat during those years. Most did not have one so your best bet is to find a good used factory one and install it.

You can install a 1985 US computer (pretty cheap used and reliable) and add the additional wiring if yours doesn't already have it to use a O2 sensor if you want to. If anything it will help with part throttle cruise and increase fuel economy.

Tom. M

I'm guessing his 85 Euro is the 16V which never came with a catalytic. There was an option for a catalytic convertor on the 86 but they had the Aussie 32V low compression engine (M28/45 I believe) and cats.
I don't think the US 32V computer would work in a 85 Euro 16V engine, but you never know until you try .

The Forgotten On

They're identical aside from the lambda input from the O2 sensor IIRC.

Tom. M

That is interesting. Would be cool to see if an O2/Cat/computer added to the dual dizzy 16V would work. I just can't see the fuel/ign maps for a 32V engine being even close to a 16V one.
Hey PorKen.......you have some spare time to test out this ?

The Forgotten On

You can just swap the chips from inside of each computer. That'll get everything right.

You only need the fuel computer though

hwyengr

CO is just one of the components modulated by a cat. Hydrocarbons and nitric oxide (and nitrogen dioxide, which is why the shorthand is NOx, covering both) very much have an odor.

I’ve got an old old car too, and idling it outside the windows next to my CO detector would raise the reading. (It was also an old old house with leaky windows)

tv

NO

That is all baloney! The boards are different, the cars are set-up different! Why would anyone destroy the best 928 set-up? Why would any1 speak about something they know nothing about.

Bnking - follow that advice and end up like "Normy" - search

Petza914

...even with the difference in clock speed between the two versions?

85euro928

You can use the US 32v LH and EZF but you need to change the chips. If you can find them I suggest using John Speakes chips. The US model ecu's had removable/replaceable chips. The '84 and earlier ecu's need to either have the chips soldered in or have the chip replaced with a socket.

jbrob007

Leave it alone... So, it smells a little bit... That's the smell of Horsepower and Torque uninhibited by the dreaded EPA

The Forgotten On

Who pissed in your cheerios? Nobody is going to post pictures of themselves in the shower

The only real difference is the 84 computer. As stated above they have odd internals. In 85 they were nearly identical. All 84-86 are LH2.2 anyway.

Why would Porsche go through the effort of having 2 different computers engineered for the same model year when a chip swap will accomplish what they needed with less effort and cost from Bosch?

Bnking

Thanks for all of the responses. I’m not a mechanic so much of it is above my head. I really just want to make sure there isn’t a safety issue.


1985 928 S Euro, 5 spd
1991 944 S2
2015 911 S, 7 spd MT
2020 Cayenne

Dmhager

One person’s odor is another’s perfume. I love the smell of unburned hydrocarbons in the morning! And the sounds of a catalyst (and mid pipe resonator) free exhaust on my 85 Euro S. Ahhhh!